Show the Dark Class historyHide the Dark Class history

The "Dark" class, or Admiralty "Type A", were designed as interchangeable MTB/MGB's and were the first Royal Naval fast attack craft to be fitted with diesel engines.  These were of course much less vulnerable than previous petrol engined craft and had a much-extended radius of action.
The boats were of composite construction, alloy framing with wooden decks and skin and could easily be changed into Torpedo Boat, Gun Boat or Minelayer configurations.
Dimensions were LOA of 71ft 8ins, Beam of 19ft 5ins, and with a 'dry' Draught of 6ft 1ins.
Normal complement were 15.  Main Armament could be 4 x 21in Torpedo Tubes, 0r 2 x 21in with a forward mounted 40mm Bofors gun.
A single 4.5ins Gun mounted on the forward mounting with a 40mm Bofors mounted aft or carry up to 16 Mines.  Displacement was 50 tons standard, 64 tons full load.

Main machinery was 2 Napier Deltic 18 cylinder marine diesel engines delivering 5000shp = 47 knots.  In later builds the Foden generator could be used to power a pre-engaged electro/hydraulic motor on the Starboard shaft for 4 knot silent running.  A total of 27 units were originally ordered by the Admiralty, spread over 7 builders including the design contractor Messrs Saunders Roe of Beaumaris, Anglesea, North Wales.  Due to a change in MOD thinking concerning Coastal Forces within NATO, nine were cancelled in 1955.

Morgan Giles built two of the class:

P1118 DARK INTRUDER 6th July 1955

P1119 DARK INVADER 5th September 1955